Problem: $\dfrac{8}{3} - \dfrac{3}{10} = {?}$
Solution: $ = {\dfrac{8 \times 10}{3 \times 10}} - {\dfrac{3 \times 3}{10 \times 3}} $ $ = {\dfrac{80}{30}} - {\dfrac{9}{30}} $ $ = \dfrac{{80} - {9}}{30} $ $ = \dfrac{71}{30}$